This invention relates to a power supply arrangement for providing auxiliary power to the electrical system of a building, such as from a standby generator or the like.
Portable generators are used in certain situations to supply electrical power to residential and commercial load circuits during a utility power outage. A system for interconnecting the generator with the load center of a building typically includes a power inlet box having a receptacle for receiving a plug extending from the generator.
The power inlet box is typically mounted to the exterior of a building, and is adapted for connection to a transfer switching mechanism which establishes an electrical path between the generator and the load center. The transfer switching mechanism typically includes a series of switches and circuit breakers, which are operable to supply power to certain selected circuits of the load center. The circuits of the transfer switching mechanism are wired to selected circuits of the load center, through wiring housed within a conduit extending between the transfer switching mechanism and the load center.
A typical transfer switching mechanism includes a housing provided with a power input receptacle. The remote power inlet box is wired to a power cord connected to a junction box, and the power cord is engageable with the power input receptacle of the transfer switching mechanism so as to provide power to the transfer switching mechanism from the generator. An alternative arrangement is illustrated in Flegel U.S. Pat. No. 5,895,981 issued Apr. 20, 1999, the disclosure of which is hereby incorporated by reference. In the '981 patent, the transfer switching mechanism includes a terminal compartment within which a set of terminals is located. The terminals are wired to the switches of the transfer switching mechanism. A set of power input wires extends from the power inlet box, and into the terminal compartment of the transfer switching mechanism. The ends of the power input wires are connected to the terminals, to establish a direct, non-plug type connection between the power inlet box and the transfer switching mechanism.
U.S. Pat. No. 6,414,240 issued to Flegel on Jul. 2, 2002 describes a power transfer switching mechanism that includes a cabinet defining an internal cavity within which a series of switches are mounted. One or more lead wires are connected to the switches, and define ends which extend into a compartment. The compartment is accessible through an opening associated with the cabinet, and a cover is selectively positionable over the opening to provide or prevent access to the compartment. With the cover removed, the lead wires can be connected to power input wires in a conventional manner, e.g., using wire-to-wire connectors, and the wires and the connectors may then be placed within the compartment and concealed by attaching the cover to the cabinet.
The present invention provides a power transfer switching mechanism that improves upon the advancements to the art provided by the '240 patent to Flegel. More particularly, in accordance with one embodiment of the present invention, a power transfer switching mechanism includes housing having a base defining an internal cavity that is segmented into first and second compartments, which may be in the form of upper and lower compartments, by an intermediate and removable wall member. The base is generally defined by a back wall and a pair of sidewalls extending outwardly from the back wall, and which may be integrally formed with the back wall. A mating engagement arrangement is interposed between the base and the intermediate wall member. The mating engagement arrangement may be in the form of a channel formed along the inner surface of the back wall and along facing inner surfaces of the sidewalls, and functions to partition the base into first and second sections, which may be an upper section and a lower section. The intermediate wall member has an opening that defines a passageway between the first and second sections for passing wires between the first and second sections.
The housing includes an enclosure arrangement that is engaged with the base and the intermediate wall member, which is configured to enclose the interior of the housing. In one embodiment, the enclosure arrangement includes a first (or upper) panel that engages portions of the sidewalls and the intermediate wall member, and that is configured to fit over the first section to define the first or upper compartment. In a similar fashion, the enclosure arrangement includes a second (or lower) panel that engages portions of the sidewalls and the intermediate wall member, and that is configured to fit over the second or lower section to define the second or lower compartment. The panels may have end wall portions that, in one embodiment, define a top and bottom of the housing when engaged with the base.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.